Circuit alarm



Oct, 16, 1928. 1,687,902

M. H. SHOENBERG ETAL CIRCUIT ALARM miiifijm IIIWIIIDIIIIIIII?" s 1 I J/flmmvm. I i r 2 BY j y AT0RNEY3 Patented Oct. 16, 1928.

PATENT OFFICE.

UNITED STATES MILTON H.8HOE11'BERG AND LESTER SCHON, OF SAN FRANCI SCO, CALIFORNIA; SAID SCHON ASSIGNOR T0 SAID SHOENBERG.

CIRCUIT ALARM? Application filed March 10, 1924. Serial No. 698,014.

Our invention is especially applicable to indicate the failure of any closed circuit to perform its customary functions.

Another object is a device interposed in an electric circuit to indicate the failure of any electrically operated device in the circuit.

Another object is adevice to indicate the burning out or theft or displacement of an electric lamp or other socket device.

Another object of our invention is an adapter constructed to be interposed between a circuit terminal device and a lamp or other electrically o erated means.

Another 0 ject is a socket device in circuit with the electrical connections of said socket which will give an alarm signal if the socket device burns out or is removed, and is especially applicable to indicate the burning out of dan er signals, as red lights in the hallways o apartment houses or hotels employed to indicate fire escapes.

Otherobjects will appear from the drawings and specifications which follow.

By referring to the accompanying drawings our invention will be made clear.

Fig. 1 is a side view of a socket adapter employing our invention. Fig. 2 is a cross section of Fig. 1 on the line II-II thereof showing the circuit connections diagrammatically.

Fig. 3 is a vertical cross section through the adapter of Fig. 1.

Fig. 4. is a conventional lamp socket to which our invention has been applied and showing the circuit connections diagrammatically.

Fig. 5 is a side view of our device adapted to be inserted at any point in a circuit and remote from a device whose operation it is desired to indicate; and is here shown as especially adapted to the dash board of an automobile for the purpose of protecting the tail lamp in circuit therewith.

Fig. 6 is a diagrammatic showing of the lamp circuit connected with the device of Flg. 5.

Throu hout the figures similar figures refer to i entical parts.

The numeral 1 indicates a terminal member adapted to be inserted in a conventional electric circuit terminal device. A conventional socket terminal connection at 2, and body portions are shown at 3 and 4, connected together at the joint or flange 5. In this case the members 1 and 2 are of metal or conducting material and form one leg of the circuit, the center connections 6 and 8 communicate with and form connections for the other leg of the circuit, these are suitably embedded in insulations 7 and 9 respectively. At 10 is an electromagnet having an armature 11 carrying a spring contact member 12 and an insulate'd arm 13. The armature is mounted upon a spring or pivoted arm 14.

The parts 12 and 14 are insulated by suitable material at 15 and 16. At 17, is a. conventional source of ener y, as a battery or dynamo. At 18 is shown lagrammatically an electric device to be energized, as a lamp.

Circuit connections are shown from the energy source 17 to the casing 3, which therefore forms one leg of the circuit, and at 20 from the casing 3 to thelamp 18. At 21 is a circuit connection from the energy source 17 to the magnet 10, and at 22 a connection from the magnet-to the other side of the lamp 18. The lamp 18 is therefore normally energized by current flowing from 17 through 19, 3, 20, thence through the lamp and back through 22, 10, 21. a

. In parallel with the magnets is the connection 23 from the casing 3 to the armature spring 12 and from the lead 22 to the arm 13. It will now be seen that if the lamp 18 burns out or is removed thus breaking the circuit between 20,22, current will flow from the energy source 17 through 19, 3, 23, 12 and through the contact. points 24, arm 13, leads 25, 22, magnet 10 and connection 21. Current will therefore flow through the magnet 10 sufficient to attract the armature 11 and to set up a buzzing because of the making and breaking of thecontacts at 24, which will \Vhen the lamp 18 is in the socket and being energized the flow of current through the magnet 10 is continuous and the armature 11 is attracted and therefore the contact points at 24 will remain separated and therefore there will be no buzzing or alarm.v It is only when the armature spring 12 and arm 11 become the active circuit and in series with the magnet and through the breaking of the lamp circuit that the buzzing is set up.

Referring particularly to Fig. 4 it will be seen that if a lamp be removed from, or

burned out in the socket 30 the alarm will at once be given by the buzzing of the mechanism contained in the socket 31.

In Figs. 5 and 6 the alarm mechanism is contained in the casing 32 having the binding posts 33, 34, and corresponding circuit connections 35, 36. At 37 is a conventional automobile battery. The connections in the casing 32 are the same as those seen in Figs. 2 and 4 whereby an opening of the lamp circuit either by the burning out or removal of the lamp at once gives the alarm to the driver in front of the automobile dash board 37, the lead 41 may be a ground connection or separately connected to the casing 32. In this latter case the device is preferably located behind the dash board and may With advantage be supported by the bracket 38 and adjusting screw 39 whereby all of the parts As an article of manufacture, a circuit alarm comprising a conductive casing adapted to form one leg of acircuit and having a socket on one side and a plug on the other side, an insulated connection in the plug and another insulated connection in the socket, an electromagnet in said casing connected between said connections, a fixed contact, an armature, for said magnet, a contact on said armature, means normally urging said contacts together, said contacts being connected between said casing and the insulated connection in the socket.

MILTON H. SHOENBERG. LESTER SCHON. 

